Water. Desalination + reuse
Issue link: https://fhpublishing.uberflip.com/i/365345
| 38 | Desalination & Water Reuse | August-September 2014 RESEARCH _________ Greg Finlayson GHD, Melbourne, David De Haas GHD, Brisbane and Dawn Guendert GHD, Irvine, California. ___ Editor's note: the quest to secure new and durable supplies of potable water is being pursued in a growing number of regions of the world as existing supplies diminish and populations grow. The authors describe here a means to appraise options that accounts for all of the chief factors in any locality that might influence a decision on how to meet the community's water requirements. AS DEMAND for water increases with growth, and water availability declines due to factors such as climate change, communities are increasingly turning to unconventional sources of water supply to augment existing supplies. We summarize here the results of a model that compares some of these options in terms of cost, energy use, and level of augmentation and draws conclusions on possible future directions. We developed four water supply augmentation scenarios for a hypothetical coastal city in Australia. The four scenarios – drawn from an earlier study by professional services consultancy, GHD, for the Australian Academy of Technological Sciences and Engineering - were: seawater reverse osmosis (SWRO) desalination; indirect potable reuse (IPR); direct potable reuse (DPR); and dual pipe reuse. Scenario 1 - SWRO desalination This involves feeding product water into a pre-existing potable water distribution system of the city. Scenario 2 - Indirect Potable Reuse (IPR) Advanced water treatment plants with treated water buffer storages are fed separately with secondary effluent from two or more centralized wastewater treatment plants (WWTPs). This is followed by recycling via a regional impoundment such as a dam that serves as the raw water source for the conventional potable supply to the city. The impoundment with its catchment and conventional potable water supply, treatment and distribution system are all pre-existing. Comparing Desalination and Recycling for Water Supply Augmentation Figure 1. Assumed configurations of the four scenarios.